Topic: Playback volume levels vs. digital input over USB or S/PDIF optical
Hi forum,
This is to ask whether I can pre-set and utilise different volume output levels at my RME ADI-2 DAC FS, depending on whether the active source is connected by USB or S/PDIF optical. Sofar, I have used this DAC only (and to my great satisfaction) in combination with an Apple Mac Mini M1, which is connected via USB, and acts as music server by running HQPlayer 4 Desktop. The latter music player not only takes care of upsampling and filtering, but also controls the output volume. Hence, the volume knob of the ADI-2 DAC is never touched – it is set at - 25.0 dBr with the output reference level at - 5 dBu (Auto), and that’s it. With output levels set in HQPlayer between - 12 and - 8 dBu I get volume levels that I find pleasant and by which I don’t force my choice of music upon my neighbours.
However, earlier this week I connected the ADI-2 DAC with my Arris VIP 5202 radio and television tuner, such by means of an optical Toslink cable. With the volume knob of the ADI-2 DAC still at - 25.0 dBr and other parameters unaltered, changing the input source at the DAC from USB to optical, leads to a volume level that is not only much too loud for me, but which has also proven sufficient to see my cats flee up the attic in horror. Obviously, in terms of volume levels, there’s quite some difference between the output of HQPlayer and the audio signal as provided over glass by my internet, television and telephony provider. Volume levels cannot be adjusted at the abovementioned Arris tuner itself; this is nothing more than a little black box with ethernet in, and HDMI and optical out. What I could do to remediate things is of course dialling down volume levels at the DAC to about - 40.0 / - 45.0 dBr, every time before I change the input source at the DAC from USB to optical (and the other way round back to - 25.0 dBr again, when playing music with HQPlayer over USB). This, though, is not the approach I’d prefer, and hence I am wondering whether there’s not a smarter solution possible.
In order to solve this problem, I did ‘RTFM’ and worked my way through RME’s excellent user guide for the ADI-2 DAC FS, in which mention is made of ‘reference levels’ (‘ref levels’). I don’t, however, immediately see how I can put these to my advantage and get at more or less the same playback volume level, regardless of whether the signal the DAC is fed with comes over USB or optical. Any ideas or suggestions as to the direction in which I should look for a solution will be warmly welcomed. Should additional information be needed with respect to my set up, feel free to let me know.
Cheers,
Simon